The Third Generation Partnership Project (3GPP) standards specify the network architecture for third and fourth generation cellular communication networks, as well as the integration between 3G and 4G networks. The standards documents specify network entities and their roles, in particular concerning the interpretation of signalling from mobile User Equipment devices, enabling the allocation of appropriate bearer channels in the Radio Access Network (RAN) of a 3G or 4G network. Work is ongoing on the specification of fifth generation network entities and their roles.
The existing standards documents require the presence of a mobile backhaul, or Mobile Transport Network. The Mobile Transport Network provides communication links implementing an IP packet service that interconnects the different network entities. The 3GPP standards specify the Mobile Transport Network as a standard IPv4 or IPv6 network. However, Software Defined Networking (SDN) offers advantages over such traditional networks in terms of flexibility and network management, and is increasingly being favoured for Mobile Transport Networks. Implementation of SDN networking involves moving a part of the control plane functionality of the Mobile Transport Network towards standard, easy to program platforms.
In order to enable smooth running of a cellular network, the Mobile Transport Network must provide sufficient capacity to allocate all forecast traffic between network entities, and to avoid congestion conditions. This may require significant over-provisioning of transport capacity to handle periods of heavy network traffic. This over-provisioning leads to increased cost and complexity in the Mobile Transport Network.